1. Field of the Invention
This invention relates to a cap and a connector unit including the cap.
2. Description of the Related Art
As a conventional cap which is mounted on a connector, there has been proposed one disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2002-124339. A receptacle connector is disposed on a printed circuit board in a state in which an opening of a fitting portion thereof is directed up, and hence it is not possible to attract the receptacle connector by a mounter. To make it possible to attract the receptacle connector by the mounter, a cap is removably mounted on the fitting portion.
The cap disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2002-124339 is mounted on an outer periphery of an upper portion of the fitting portion in a manner covering the opening of the fitting portion.
As another conventional cap, there has been proposed a cap which is comprised of an insertion portion having a hollow cylindrical shape, which is inserted in a fitting portion of a receptacle connector, and a cover portion which covers an opening of the fitting portion. The insertion portion and the cover portion are integrally formed of a resin.
Further, a receptacle connector of a certain type includes a locking spring for preventing a plug connector from coming off. A front portion of the locking spring protrudes into a fitting portion of the receptacle connector. When the plug connector is fitted to the receptacle connector including the locking spring, the locking spring of the receptacle connector is engaged with a hole of the plug connector, whereby the plug connector is locked to the receptacle connector.
If the cap is mounted on the receptacle connector, it is possible to attract the receptacle connector by the mounter via the cap, to thereby dispose the receptacle connector on a predetermined position on the printed circuit board. It should be noted that when the cap is mounted on the receptacle connector, the locking spring of the receptacle connector presses the outer peripheral surface of the insertion portion of the cap, whereby the cap is positively held by the receptacle connector.
The printed circuit board on which the receptacle connector is disposed is conveyed to a reflow furnace, and the receptacle connector is soldered to the printed circuit board.
However, since the cap is made of a resin, if the cap is heated in the reflow furnace, the cap is liable to be deformed, and further, in a case of a connector provided with a locking mechanism, the stress of the locking spring is applied to the outer peripheral surface of the insertion portion of the cap, and hence the cap is further deformed.
As a consequence, for example, when the printed circuit board is conveyed after the receptacle connector is soldered thereto, or when the printed circuit board is inverted upside down to mount other electronic components on a surface opposite to a surface on which the receptacle connector is mounted, there is a case where the cap falls off the receptacle connector.